Words such as “phenomenal” and “special talent” were thrown around by media analysts last week after star defensive end and potential No. 1 overall draft pick Jadaveon Clowney participated in his 15-minute Pro Day workout in front of dozens of scouts on the University of South Carolina campus.

Heisman-winning quarterback Johnny Manziel, meanwhile, received reviews such as “impressive” and “dazzles” at his Pro Day two weeks ago at Texas A&M, supposedly vaulting himself into contention for the No. 1 pick, as well.

Pro Days garner the NFL headlines in March and April, but the reality is these Pro Day workouts will mean very little to teams in their evaluation of the two prospects. Quarterback workouts, especially, are more sideshow than legitimate football event. The workout is run by the quarterback’s personal coach, the throws are scripted and practiced several times in advance, and the player isn’t throwing against a defense.

Manziel’s workout included an appearance by former president George H.W. Bush and wife Barbara, a soundtrack by rapper Drake, and a personalized outfit that Nike put on sale immediately after the workout.

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“It’s a media sideshow,” said Greg Gabriel, the former college scouting director for the Bears and NFL scout for 30 years. “You don’t put a whole lot into it, other than obviously he’s got to complete the passes and you want him to throw a tight ball. But it’s not football. It’s playing against air.”

Pro Days are often used as a final justification for drafting or not drafting a player, but often the scouts can watch a workout and come away with many, varied opinions.

“If you want to like a guy, then you’re going to point to his Pro Day and say, ‘See, look at how good he looks,’ in a scripted workout with no decision-making involved and no duress involved,’” said Louis Riddick, an ex-cornerback and scout who is now with ESPN. “People who like certain players point to these Pro Days as justification for them liking them, when really they have no relevance as it pertains to how they’re actually going to perform on Sundays in the NFL.”

That’s not to say Pro Days don’t have any value. They are one of the few times coaches and scouts can get a close look and have personal interaction with prospects — NFL position coaches always run the Pro Day drills for every position other than quarterback. Pro Days are also a good way to check out players who were injured and did not participate at February’s combine, or to scout some of the lesser-known prospects that could help a team at the back of the draft.

One NFL executive with a top-10 pick outlined a few areas in which Pro Days can help:

■ Get to see the athletes perform skills they didn’t do in college, such as Clowney displaying drop-back coverage.

■ See what kind of condition the players are in, knowing that the NFL scouts are watching.

■ See how much the players have improved (or the opposite) since the combine, an indication of work habits.

■ See how they interact with coaches, scouts, and teammates, and in a competitive environment.

Still, the Pro Day is only a tiny piece of the overall scouting equation.

“At the end of the day, the tape and the fall grades are the most important grades,” the executive said.

Pro Day workouts generally consist of combine testing — bench press, vertical jump, 40-yard dash — as well as agility drills specific to positions, and can last from 15 minutes to an hour. A good Pro Day is expected, given the controlled environment, and a mediocre one can set off red flags, particularly at quarterback.

Louisville quarterback Teddy Bridgewater, also a candidate for the No. 1 pick, has many analysts rethinking their rankings after turning in a less-than-crisp Pro Day last month. Most teams, especially those that need a quarterback at the top of the draft, won’t panic over Bridgewater’s shaky day, but they will go back and watch his film more closely and reevaluate his draft grade.

“It may be indicative of a bigger problem, or it may have just been a bad day,” said Riddick. “You never want to ever go 180 from your original evaluation based off of a Pro Day, ever. It should never make you flip-flop or change your opinion. But it will make you go back and reevaluate and watch more film and make sure you’re not missing something.”

While Pro Days get all of the attention, it’s the private workouts afterward that really matter. Teams only have the ability to work out players on campus or in their hometowns, and the private workout is the team’s chance to test the players on the field and in the classroom in an unscripted environment.

The Browns, picking No. 4 overall and widely believed to be in the quarterback market, haven’t even bothered attending any of the Pro Days of the top prospects. But they’re working each player individually and likely bringing them to Cleveland for visits with coaches and top personnel.

“Cleveland is on the right page with this,” Gabriel said. “Now it’s more of a reactive than prepared workout. The Cleveland coaches are running the workout, the quarterback doesn’t know what to expect. They can put him in the meeting room, put him on the board, teach him some things, see how fast he can repaint it, and then carry it over to the practice field right away.”

JOB HUNT

Gilbert aggressively pursuing union post

Former defensive tackle Sean Gilbert had 42½ sacks in 11 NFL seasons, and now he’s aiming to take down Players Association executive director DeMaurice Smith with some pretty eye-opening numbers, if they are to be trusted.

Gilbert, a vocal opponent of the job Smith did in negotiating the 2011 collective bargaining agreement, which runs through 2020, is preparing to challenge Smith for his job when a vote is held in 2015. Gilbert met with several agents at the combine to recruit the support of their players, and last week circulated an e-mail to the agents outlining his problems with the CBA and his steps to fix it.

The Globe obtained a copy of the e-mail, and among Gilbert’s claims:

“1. Under Gene Upshaw, the salary cap would have been $157 million this year instead of $133 million. That is a shift of $768 million from players to owners THIS YEAR ALONE.

“2. Through the first four years of this Collective Bargaining Agreement more than $2.5 billion has already shifted from the players to the owners.”

There is no math behind Gilbert’s numbers or a way to verify his numbers, but he says they explain why owners paid Goodell $73 million in salary over the first two years of the new CBA. Gilbert calls it Goodell’s $73 million “tip.”

For background purposes, the league’s salary cap was expected to be $135 million in 2010 before the owners opted out of the previous CBA. They had an uncapped season in 2010 and then reset the salary cap at $120 million for 2011. The cap remained relatively flat for three seasons before jumping to $133 million for the 2014 season, and could jump as high as $160 million for the 2016 season based on the spike in TV revenues.

Gilbert, a close personal adviser for Patriots cornerback Darrelle Revis who helped him stage a successful contract holdout in 2010, said he is “in the process of drafting a platform” for his candidacy for the NFLPA top job. The platform seems to be centered around two ideas — that the players can terminate the CBA because of collusion, and a new concept called the “Contract Dissolution Benefit,” which he didn’t explain. Gilbert made clear that he isn’t advocating a player strike.

Gilbert likely will have an uphill battle proving any owner collusion in court, and Smith appears to still have good support among players.

WINNING NOTE

Belichick lays claim to a big-money idea

Bill Belichick left his imprint by popularizing the 3-4 defense with
Lawrence Taylor and the Giants and is starting to leave his imprint on the league’s bylaws by suggesting several rules changes at the owners’ meetings last month.

Not surprisingly, Belichick also is responsible for a popular scouting trick teams use on quarterback prospects — or at least so he claims.

In the new movie “Draft Day,” in which Kevin Costner wheels and deals as general manager of the Browns, one of the methods the Browns used to judge quarterbacks was to give each a playbook and tape a $100 bill to the last page.

The quarterbacks were then asked to send the playbooks back, and if the $100 bill was still there, the team knew the prospect didn’t read the entire playbook or had lied about doing so.

Ivan Reitman, the movie’s director, appeared on comedian Dennis Miller’s syndicated radio show last week and spoke about how that detail was added to the flick.

“Denis [Leary] actually went to Bill Belichick for help,” Reitman said of the movie’s other star, who plays the Browns’ coach. “He told him we had the story — you’ll know it when you see it — of the $100 bill. Belichick said, ‘How’d you know about that?’

“And Belichick said, ‘Look, I invented that.’ I think a coach who worked under Belichick told our writers that story, and we put it in there, and it’s very effective where it’s placed.”

ETC.

Ravens’ offseason pales to that of rivals

The Ravens have had a fairly productive offseason, re-signing almost all of their key players in Terrell Suggs, Dennis Pitta, Eugene Monroe, and Daryl Smith, and adding Owen Daniels and Steve Smith in free agency. And they’re only a little more than a year removed from winning the Super Bowl.

But even coach John Harbaugh acknowledged that the Ravens’ moves pale in comparison to those made by the Patriots and Broncos, who loaded up with players such as
Darrelle Revis, Aqib Talib, DeMarcus Ware, Brandon Browner, Julian Edelman, and T.J. Ward.

“I was disappointed with the moves that the Broncos and Patriots made in the offseason,” Harbaugh joked at the owners’ meetings. “I thought they did a great job and that disturbed me.”

Perhaps Harbaugh is using this as a motivational ploy for his players, but he clearly has a lot of respect for both the Patriots and Broncos, who should enter next season as the favorites to again play in the AFC Championship game. “They’re already supremely talented teams. So, it just puts them at the top,” Harbaugh told Pro Football Talk. “They’re the teams that we’re hunting at this time. We’ve got to catch up with those guys.”

Cupboard is far from bare

Free agency is almost four weeks old and most of the top players have been snapped up. But a few intriguing names remain available, led by running back Chris Johnson, who was released by the Titans on Friday. The best players available:

Is there more to it?

Speaking of players without a team, one interesting situation to watch is that of Eric Winston, an eight-year veteran who spent last year with Arizona.

Winston, 30, was recently elected president of the NFLPA, succeeding
Domonique Foxworth. Neither of the last two presidents were able to find spots with teams after being elected — Foxworth was elected in 2012 and last played in 2011, while Kevin Mawae was forced into retirement after being elected in 2010.

Perhaps Winston’s unemployment is because of shaky play – ProFootballFocus.com rated him as the 69th-best offensive tackle out of 74 last season — but Mawae openly questioned if he was being blackballed, and it’s fair to wonder if the same could happen to Winston.

This one bigger and better

Seahawks coach Pete Carroll, who signed a three-year contract extension through 2016 on Friday, joined
Jimmy Johnson and Barry Switzer as the only coaches to win championships in college and professional football. Carroll was asked at the owners’ meetings to explain the difference between the two championships (Carroll won the BCS title for the 2004 season with USC).

“The parade was way bigger [after the Super Bowl],” he joked. “During the process of it it’s not much different, I commented after the game that it felt pretty similar. But the magnitude of it seems more significant, and it affected more people, and it’s more obvious that you’ve done something special.”

A good example

The Patriots have been known to play hardball in contract negotiations, but one player they should lock up to a long-term deal sooner rather than later is free safety Devin McCourty.

Football and cap-wise, it makes a lot of sense. McCourty, entering his fifth season, developed into one of the league’s best free safeties last year, and a contract extension could lower his $5.115 million cap number for the final year of his rookie deal.

But more importantly, McCourty has been an exemplary representative of the Patriots, and with the organization sensitive to off-field issues following the murder charge of Aaron Hernandez, McCourty is just the type of player the team should want to keep.

In two-plus months this offseason, McCourty held a casino night to raise funds and awareness for sickle cell research, appeared at an elementary school two weeks ago, appeared at Boston Children’s Hospital last Monday to shoot a video about sickle cell, and on Wednesday helped launch a food drive to help needy families receive
milk.

“My mom always told me you have to do something to show how blessed you are and to help other people,” McCourty said. “I feel like we gain so much in life, and there has to be a reason for it. I think it gives you a platform to do great things, not just play football, and it allows you to affect people’s lives in a bigger way.”

Ben Volin can be reached at ben.volin@globe.com. Follow him on Twitter @BenVolin. Material from interviews, wire services, other beat writers, and league and team sources was used in this report.

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